Which muscle is NOT innervated by the Musculocutaneous nerve?

• A. Brachialis
• B. Biceps Brachii
• C. Coracobrachialis
• D. Triceps Brachii

Answer: (D)

Understand that the Musculocutaneous nerve supplies the flexor muscles in the anterior arm: coracobrachialis, biceps brachii, and brachialis. The triceps brachii, on the other hand, is a posterior arm muscle that extends the elbow and is innervated by the radial nerve. Therefore, triceps brachii is not innervated by the Musculocutaneous nerve. If the Musculocutaneous nerve is affected, elbow flexion weakened while triceps function remains (assuming the radial nerve is intact).